Process of washing gases for rapidly freeing them from dust or smoke held in suspension therein.



I P. KESTNER. PROCESS OF WASHING GASES FOR RAPIDLY FREEING THEM FROM DUST 0R SMOKE HELD IN SUSPENSION THEEEIN.

APPLICATION FILED MAY 4, 1906. RENEWED MAR. 23,1911.

991,157., Patented May 2,1911.

Chub/4. L @LMM UNITED STATES ATET UFFICE.

P AUL KESTNER, O13 LILLE,'IERANCE.

PROCESS OF WASHING GASES FOR RAPIDLY FREEING THEM FROM DUST OR SMOKE HELD IN SUSPENSION THEREIN.

Specification of Letters Patent.

Patented May 2, 1911.

Application filed May 4, 1906, Serial No. 315,263. Renewed March 23, 1911. Serial No. 616,489. A

To all whom it may concern.

Be it known that. l, Pam. Kns'rnnn, a citizen of the French tepublie, residing at Lille. in the Nord Province of France, have invented a new and useful Improved Process of \Vashing (lases for Rapidly Freeing Them from Dust or Smoke Held in Suspension Therein, of which the following is a specification.

This process is specially applicable for rapidly washing large volumes of gases holding in suspension dust or smoke very diflicult to absorb in water, such as blast furnace gases or the combustion gases emanating from coal-consuming furnaces.

It is an established fact that most kinds of dust when dry have a very characteristic repulsion for water, but on the other hand when they have been preliminarily moistened or dampened they are attracted by water and readily absorbed thereby. My process recognizes this and is based upon the following observation: If steam be intimately mixed with a gas in which line dry dust is held in suspension, the particles of dust are not moistened even if they remain mixed up with the steam for a very long time; but if the gas be cooled the steam condenses instantly upon the particles of dust and wets them. They can thus immediately after be absorbed very readily in water.

I am aware that the employment of steam to assist in the washing of gases is no new thing, but heretofore the steam has been employed hop-hazard, without taking into account how it acts. It was not recognized that in order that the steam might have an instantaneous action two essential conditions were necessary: let, that the steam must be intimately mixed with the gases, and 2nd, that the mixture must be cooled throughout in order that the steam might condense on all the particles to be absorbed. Further, the processes in which steam has been employed apart from these essential conditions have been both slow and incomplete, and not rapid and thorough like that here described. Steam does not act upon dust to wet it so long as it remains in the state of steam; it only acts when there is condensation of the steam.

The process can best be seen and understood in the light of the apparatus which is the best known to me for practicing it.

Referring to the drawings :Figure 1 shows the apparatus in plan. Fig. 2 represents a cross section on the line 22 of Fig. 1.

In the drawings :A represents a chambered receptacle divided into three compartments a, a, a Upon this receptacle are mounted a series of casings a a a. The interiors of these casings are in connection with the respective compartments. In the casings, respectively, are mounted the respective fans B, B B Each of these fans is mounted upon a shaft 6 extending through the wall of its casing and turning in bearings b Each shaft is turned by a pulley b -mountedupon the shaft. Connecting with the side of the casing a to inlet into the eye of the fan B is a pipe a. Extending from the compartment or chamber a to connect with the side of the casing a and inlet into the eye of the fan B is a pipe a. Extending from the compartment (4 to connect with the side of the casing a and inlet into the eye of the fan B is a pipe a From the compartment (4 there extends an outlet pipe (4.

Alongside the receptacle A are a series of tanks 0 c which act as receptacles for containing water or other fluid to be supplied to the respective fans and as retorts, also, for receiving the contents of the respective chambers a, a a by the way of the series of pipes a a, a which extend, respcctively, from the bottoms of the compartments a, a, a and empty into the respective tanks. Into the tank 0 there empties a pipe 0 by which water may be poured into this tank and also into all the tanks, the arrangement being such that the water will flow over the partitions from the tank 0 into the tank and thence into the tank 0 and outlet from this tank through an overflow pipe 0 I), I), 1) represent a series of pumps. These pumps conn'ect with the bottoms of the respective tanks; the pump D with the bottom of the tank 0 through a pipe (1, the pump 1) with the bottom of the tank a by a pipe (1, and the pump 1) with the bottom of the tank 0 by a pipe (F. From these pipes there extend, respectively, pipes d, (1, (F. The pipe 11"- extends up to outlet into the eye. of the fan B; the pipe (I outlets into the eye of the fan 13. and the pipe (I outlets into the fan B Steam may be supplied from a suitable source by the pipe (F.

\Vith this apparatus the process is car- 35 ments a thence by the way of the pipe a ried out in the following manner:-The

smoke or other matter to be treated is introduced through the pipe a into the eye of the rotary fan B. Steam is at the same time introduced to mingle with the gases and in a manner whereby it may become intimately mixed therewith by the action of the fan. The introduction of steam may be obtained, when the gases to be treated are at a high temperature, by the injection of water into the fan by the way of the pipe d with the effect that the water will be broken up into fine particles by the blades or wings of the fan and thereupon be converted into steam by the heat of the gases through the action ofthe fan; or if the initial temperature of the gases to be treated is not sufficiently high, steam may be introduced into the fan by way of the pipe (2. From this first fan the intermingled steam and gases pass into the compartment or chamber a and thence by the way of the pipe a into the eye of the fan 13. Water is at the same time thrown into the fan by the way of the pipe d*. This water is drawn from the tank a and is cold or te )id. It is finely divided by the fan and intimately mixed with the steam-laden gases passing through the fan by which intermixture the gases are cooled regularly throughout all their volume and the steam condensed on the particles of dust, thus moistening them and rendering them in a condition to be absorbed or retained by water. From the fan B the moisture-laden gases pass into the compartinto the fan B where the final washing takes place. This washing is accomplished by water thrown into the fan by the way of the pipe (i The moistened particles of dust condense then rapidly in the water which is broken up into minute particles by the blades of the fan and intimately mixed with the gases, thus presenting a large absorbing surface. After this final washing the gases thus cleansed pass into the compartment a and thence out. through the outlet pipe a".

As the passage of the gases through each fan only occupies a fraction of a second, the gases can be completely purified or cleansed in a very short space of time, hardly exceeding one second for all three stages' The process is suitable for all gases containing impurities which can be absorbed by water. The centrifugal fan washers may be replaced by any other apparatus by means of which an intimate and rapid mixing of the gases with steam and water can be accomplished. Centrifugal fan washers have, however, an advantage in that. they accomphsh the mixing thoroughly and at the same time serve as exhausters or propellers.

What I claim as my invention and desire to secure by Letters Patent of the United States is:

1. The process of cleaning gases to free them from dust, smoke, or other impurities conslstlng in intimately mixing steam with the gases by subjecting the steam and gases combined to the action of a rapidly moving surface, then cooling the mixture throughout its mass or volume to cause said steam to be condensed upon said impurities, and

then washing in Water acting as an absol-bent.

2. The process of cleaning gases to free them from dust, smoke, or other impuritiesconsisting in intimately mixing steam with the gases by subjecting the steam and gases combined to the action of a rapidly rotating body, then cooling the mixture throughout its mass or volume by intimately mixing water therewith to cause said steam to be condensed upon ,said impurities, and then washing in water acting as an absorbent.

3. The process of cleaning gases to free them from smoke, dust or other impurities consisting in intimately mixing steam with gases by subjecting the steam and gases combined to the action of a rapidly rotating body, then immediately cooling the mixture throughout its mass or volume by intimately mixing water therewith by the action of a rapidly rotating body to cause the steam to be condensed upon the impurities in the gases and then immediately washing the gases and moistened particles with water acting as an absorbent, the water being intimately mixed with the gases and particles by the action' of a rapidly rotating body.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses. a

- PAUL KESTNER.

Witnesses:

CIIARRIER PRENN, Lion PECKEL. 

